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1.
Abstract

Accessibility of library electronic resources is a must. Its importance derives from professional ethics of librarianship, rising total costs of acquisition, and mounting legal challenges to colleges and universities that fail to provide resources accessible to users with disabilities. Library staff are responsible for ensuring the accessibility of vendor-licensed eresources. This column reviews the accessibility clauses of nine model license agreements for electronic resources. It describes terms that should go into an optimal accessibility clause and creates a composite model clause. It also provides guidance for library staff seeking to negotiate stronger accessibility language into vendor license agreements. Finally, it addresses the impact of accommodation requests on the total cost of acquiring library eresources, concluding with a call to redouble efforts to advocate for greater accessibility and educate both vendors and library staff about its importance.  相似文献   
2.
一种基于闭排队网络的集装箱码头设备配置优化模型   总被引:5,自引:0,他引:5  
将集装箱码头龙门吊装卸工艺抽象为闭排队网络模型,采用估算均值法计算了顾客到达和服务时间分布为一般情况的闭排队网络系统性能指标.仿真结果表明,闭排队网络模型计算结果可以为集装箱码头设备配置提供一定的决策支持.  相似文献   
3.
在分析了聚合物驱提高采收率技术在实际应用中的局限性基础上,提出了采用就地起泡形成泡沫的泡沫增强聚合物体系以减小聚合物沿大通道窜流的问题。为了有效确定该体系的配方,实验中采用了均匀设计实验方法安排实验,并运用DPS数据处理软件对实验数据进行了二次多项式逐步回归处理,找出了影响该体系性能的主要因素。  相似文献   
4.
ABSTRACT

Considerable effort has been spent on the development of confidence intervals for process capability indices (PCIs) based on the sampling distribution of the PCI or the transferred PCI. However, there is still no definitive way to construct a closed interval for a PCI. The aim of this study is to develop closed intervals for the PCIs Cpu, Cpl, and Spk based on Boole's inequality and de Morgan's laws. The relationships between different sample sizes, the significance levels, and the confidence intervals of the PCIs Cpu, Cpl, and Spk are investigated. Then, a testing model for interval estimation for the PCIs Cpu, Cpl, and Spk is built as a powerful tool for measuring the quality performance of a product. Finally, an applied example is given to demonstrate the effectiveness and applicability of the proposed method and the testing model.  相似文献   
5.
Online material and waste exchanges (OMWEs) provide online channels to repurpose by‐products, unused materials and waste from industrial and commercial facilities. Unfortunately, OMWE's also have challenges. First, sellers may have access to other disposal options and, as a result, may not fully commit to the exchange. Second, buyers can face high uncertainty about the product exchanged and the transaction being undertaken. Overcoming these challenges is the “last hurdle” to making OMWEs successful. This study investigates the factors that reduce the buyers' uncertainty and increase the sellers' commitment to the OMWE. We analyze novel transaction‐level data from an online exchange (MNExchange.org) combined with other archival public records on county‐level repurposing and disposal statistics. First, we find that regional repurposing policies and alternatives have a complementary effect on sellers' commitment toward OMWEs, resulting in increased OMWE exchanges. However, regional disposal policies and alternatives have a substitution effect on sellers' commitment, resulting in reduced exchange success. Further, greater product and transaction information reduce the buyer's uncertainty and increase exchange success. Finally, the analysis shows that users' (buyers and sellers) heavily rely on their prior experience with OMWEs. Specifically, higher familiarity between the buyer–seller pair and familiarity with the OMWE system leads to higher likelihood of exchange success. This study lays the foundation for understanding OMWEs and has important implications for developing policies and operations to increase online transactions of by‐products, materials and wastes.  相似文献   
6.
We present a unifying approach to multiple testing procedures for sequential (or streaming) data by giving sufficient conditions for a sequential multiple testing procedure to control the familywise error rate (FWER). Together, we call these conditions a ‘rejection principle for sequential tests’, which we then apply to some existing sequential multiple testing procedures to give simplified understanding of their FWER control. Next, the principle is applied to derive two new sequential multiple testing procedures with provable FWER control, one for testing hypotheses in order and another for closed testing. Examples of these new procedures are given by applying them to a chromosome aberration data set and finding the maximum safe dose of a treatment.  相似文献   
7.
泡沫经济是市场经济发展中的一个客观必然现象,无疑,泡沫经济有害无利。本文从资产市场角度,用统计推断理论,来构造泡沫经济预控方法。  相似文献   
8.
通过文献参阅,运用现代经济学和社会学相关理论和方法,探索性地分析集体耕作制时期,农地产权残缺、社会的高度封闭性及平均分配主义的影响和中国农村人口的快速增长。改革开放30年来,影响中国农村人口快速增长的诸因素和人口低生育水平反弹的压力基本消除。面对人口长期负惯性增长的新趋势,中国应及时调整生育政策。  相似文献   
9.
村民自治模式具有封闭性自治的特点。在现代化进程的强烈冲击下,农村社会已经发生历史性变迁,农村社会逐步走向开放性与异质性,村民自治赖以存在的经济与社会基础逐步瓦解。农村经济与社会变迁的既有现实决定了必须建立适应当前农村社会开放性、流动性社会要求的新型自治实践模式。由“开放性自治”到“封闭性自治”的转型是农村基层民主发展的演进逻辑。  相似文献   
10.
采用Si、Mg及Cu元素进行合金化处理,制备了几种不同力学性能的开孔泡沫铝,通过准静态压缩实验研究了合金化对泡沫铝压缩力学行为的影响。实验结果表明,采用Si、Mg及Cu元素合金化处理显著改变了泡沫铝的应力-应变行为。  相似文献   
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